Re: phpBB or Vbulletin?
vBulletin all the way, it's a superior commercial grade product, unlike phpBB which is unsupported open source. It would literally take you countless hours of hacking to bring a default phpBB up to the level of default vB, you can't even merge threads together with default phpBB.
I've used Invision PowerBoard, vBulletin and phpBB at various times for forums that can have 1,500+ people on at any given time, vBulletin is the superior product. PM me if you need more info.
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